Dispensers for open spring retaining rings



June 28, 1966 H. ERDMANN 3,253,158

DISPENSERS FOR OPEN SPRING RETAINING RINGS Filed Feb. 2, 1965 3 Sheets-Sheet 2 go 66a,

Bat/04AM ATTORNEY June 28, 1966 ERDMANN DISPENSERS FOR OPEN SPRING RETAINING RINGS 5 Sheets-Sheet 5 Filed Feb. 2, 1965 N VENTOR NAG iii

United States Patent "ice 3,258,158 DISPENSERS FOR OPENGSSPRIN G RETAINING RIN Hans Erdmann, Maplewood, N.J., assignor to Waldes Kohinoor, Inc., Long Island, N.Y., a corporation of New York Filed Feb. 2, 1965, Ser. No. 429,758 8 Claims. (Cl. 221220) This invention relates to improvements in dispensers for open spring retaining rings, particularly of the bowed type provided with locking prongs as disclosed and claimed in United States patent to Wurzel No. 2,755,698, dated June 24, 1956.

As explained in my prior Patent No. 2,900,107, dated August 18, 1959, the dispensing of open bowed rings provided with locking prongs one at a time from a supply of such rings disposed on and held in stack formation by the generally vertical stack rod of a dispenser, through the use of a so-called applicator designed both to pick off the lowermost ring of the stack and thereafter to assemble said ring in the groove of a shaft, spindle and the like, involves special problems not present in the dispensing of either plane open rings or even bowed rings which are devoid of the aforesaid locking prongs. That is to say, to pick off the lowermost bowed ring provided with locking prongs from a stack of such rings, the next higher ring of the stack (and of course all rings above same) must be lifted by an amount as to dispose said next higher ring above said lowermost ring, since otherwise the prongs of the lowermost ring will catch on the next higher ring and intended ring withdrawal will be impeded.

According to my prior patent, the lifting of the ring next above the lowermost ring was, generally speaking, achieved by push or thrust exerted on the forwardly disposed outer edge of said next higher ring by the front end edges of the applicator as the latter is inserted in the dispenser, such forcing said ring to move rearwardly and, in so doing, to ride up an incline disposed in the path of the inner edge of the body of said ring, such in effect camming said next higher ring of the stack to a level above that of the lowermost ring and its prongs.

However, although performing in general satisfactory manner, continuing experience with the dispenser constructed according to my aforesaid patent revealed an undesirable uncertainty in its operation, particularly in the case of the rings being thin and tightly stacked and/or because of the tendency of the rings of the stack thereof to incline forwardly-downwardly. Under these conditions, it is possible for the applicator to pick off two or even three rings, for example, rather than the single lowermost ring from the ring stack. Another cause of some uncertainty of operation characterizing my aforesaid prior dispenser was the difficulty in inserting the applicator in the dispenser with the precision necessary to dispose the ringreceiving recessed seat of the applicator precisely in the plane of the lowermost ring to be dispensed and similarly to dispose the front end edges of said applicator precisely at the level such that they will exercise their thrust action cleanly and squarely against the outer edge of the next higher ring, as makes for a positive separation of said next higher ring from the lowermost ring.

Stated broadly, a major object of the present invention is the provision of a dispenser for bowed open spring retaining rings having locking prongs, of the type generally disclosed and claimed in my aforesaid Patent No. 2,900,- 107 and which is further characterized by its ability to effect a clean separation of the rings disposed above the lowermost ring, and especially the next higher ring, of the stack thereof from said lowermost ring, responsive to insertion of the application, as insures certain pick-off of said lowermost ring by said applicator and facilitates and speeds up the ring dispensing operation.

3,258,158 Patented June 28, 1966 Another important object of the invention is the provision of a dispenser for open bowed retaining rings having self-locking prongs as aforesaid which, while operating on the general principles of the dispenser for such rings disclosed and claimed in my prior Patent No. 2,900,107, is further provided with means actuable by the applicator in its movement toward lowermost-ring pickoif position to effectively isolate said ring from the next higher ring or rings, and to achieve this desirable result without the applicator making any direct contact with said next higher ring, as was a requirement of my earlier dispenser.

More particularly, an object of the invention is the provision of an improved dispenser as aforesaid constructed and arranged so as to be capable of effecting both upward and rearward movement of the retaining ring next above the lowermost ring of the stack thereof in the dispenser to a position as insures free and unimpeded withdrawal movement of said lowermost ring past said next higher ring by the applicator, and without any requirement for the applicator making direct contact or engagement with said next higher ring.

Yet another object of the invention is the provision of a dispenser as aforesaid characterized by the incorporation of means separate from but actuable by the applicator during the course of its inserting movement for exerting rearward push or thrust on a ring or rings of the stack spaced well upwardly from the lowermost ring, as effects positive rearward flexing of the lower end of the dispenser stack rod to a position insuring a clean separation of said lowermost from the next higher ring of said stack, as in turn makes certain that said applicator will pick oif only said lowermost ring.

Still a further object is the provision of a ring dispenser of the stated character which incorporates improved applicator guide means functioning positively to guide the applicator, when being inserted into the dispenser, to a position in which its working end is in exact horizontal alignment with the lowermost ring of the stack thereof stored in the dispenser.

The above and other objects and features of advantage of the improved retaining ring dispenser according to the present invention will appear from the following detailed description thereof, taken with the following illustrative drawings, wherein:

FIG. 1 is a side elevation, FIG. 2 is a top plan view, and FIG. 3 a front elevation of a dispenser according to the invention, FIG. 1 further showing a ring applicator for operating same in the correct position for insertion and ultimate ring pick-up, to which it has been guided by the guide-means attachment as herein contemplated;

FIGS. 4 and 4A are fragmentary, part-sectional plan and side views which depict the dispenser stack rod in its neutral (normal forward) position and the applicator moving toward the means of the invention for insuring .a clean pick-off of the lowermost ring of the stack thereof;

FIGS. 5 and 5A and FIGS. 6 and 6A are views similar to FIGS. 4 and 4A but illustrating the progressive stages of the lowermost ring isolating and pick-off action effected by the applicator as it moves to its fully inserted position; and

FIG. 7 is a perspective view of the ring-stack support means embodied in the herein dispenser.

Referring to the drawings in greater detail, it will be seen from a consideration of FIGS. 1-3 inclusive that the dispenser of the present invention is basically similar to that disclosed in my aforesaid Patent No. 2,900,107, in that it comprises a generally vertical stack rod 10,

illustratively an elongated leaf spring whose lower end portion is stiffened by front and rear reinforcing strips 12a, 1212 (see FIG. 4, for example) and which is secured at its upper end only to .the forward edge of an upright bracket 14, in turn secured by means of a horizontal foot flange 16 to the upper horizontal surface of a raised block-like formation 18 on a plate-form base 20, which latter may be and is usually fixedly secured as by bolts or screws to a work bench or table. As shown in broken lines (FIG. 1), a separable stack rod extension-part 22 may be hooked to the bracket 14 above and in vertical alignment with the stack rod proper as by means of the upwardly inclined hooks 24, 2401, said extension functioning to increase the effective length of the stack rod as enables it to mount a substantial supply of the rings R to be assembled disposed in vertical column or stack formation on said stack rod and its aforesaid extension part 22.

As best seen in FIGS. 4 and 4A, said rings R to be dispensed are of the bowed open type provided with locking prongs enabling the ring to self-lock itself to the peripheral surface of the shaft or spindle along the groove thereof into which the body of the ring is assembled, all as disclosed in the aforesaid Wurzel Patent No. 2,755,698, to which reference may be had for constructional details and manner of operation of such a ring. Speaking generally, however, each of the rings R comprises an open-ended ring body having a wide gap between its open ends as characterizes the open retaining ring and it is bowed about its vertical center line, i.e. the center line extending through the ring-body middle section, the ring center, and thence the gap, so that it has concavo-convex section transversely of said center line, and it is further provided with locking prongs p and 11 (FIG. 4) at approximately the junctions between the ends of its arcuate inner edge and the inner straight edges of the ring ends which define the ring gap. Preferably, the rings R are each also provided with diametrically aligned notches n and 11 disposed intermediate said prongs and the ring inner-edge proper, into which the side edges of the stack rod extend, such arrangement serving to properly orient the rings on the stack rod and further insuring that the rings will be positively moved in their plane with flexure of the stack rod. Illustratively, the rings R are also each provided on opposite side edge portions with coplanar side wings W, W2 which serve to stabilize the ring when it rests on a flat surface with its convex face upwardly disposed.

From the above and as depicted in the drawings, it will be understood that a dispenser of the type under consideration is adapted to mount a substantial supply of the rings R to be dispensed, arranged with their convex faces upward and with their locking prongs also pointing upwardly and moreover oriented so that their gaps open to the rear of the stack rod 10, in generally vertical stack or column formation on said stack rod.

To provide a proper support for the stack of bowed rings so mounted and disposed on the stack rod, a specially designed supporting part secured to the top surface of the base block 18 beneath said stack rod is provided. By reference to FIG. 7, such illustratively comprises a horizontal plate member 28 having on its upper face a centrally disposed front-to-rear rib-like formation 30 defined by converging side walls 30a, 30b and a fiat top surface 300, and projecting upwardly from said flat top surface another rib-like formation 32 of lesser width than the rib-like formation 30, and which is defined by vertical side edges 32a, 32b and a flat top surface 32c, and by semi-circular nose-like front-end edge surface 32d. The rearward end of the upper rib-like formation 32 terminates in a lug of increased height, the forward face of which defines a forwardly-facing vertical stop shoulder 32c. Also to be noted is that there is provided, in both the front edge of the support plate 28 and similarly in the front-end edge of the rib-like formation 30, a common cut-out 36, and that the semicircular front-end edge 32d of the second or upper rib like formation 32 is set back from said cut-out. FIG. 7 further illustrates that said semi-circular front-end edge is vertical for about the lower half of its height, thus to define an abrupt rounded shoulder designated 32 and is chamfered or inclined rearwardly for the upper half of its height, thus to define a camming edge designated 32g.

By properly dimensioning the width and height of said rib-like formations 30 and 32, the forwardly projecting portion of said lower rib-like formation 30 is adapted to serve as a rest for the middle-section of the lowermost ring of the stack when the side wings W and W2 thereof are resting on the support plate 28, the ring gap meanwhile accommodating the rearward-end portion of said rib. By design, the extent of set-back of the front-end edge 32d of the second-named or upper rib-like formation 32 from the front-end edge of the lower ri'b 30 (as defined 'by the bottom of the cut-'out 36) is less than the radial dimension of the said middle-portion of the ring, and thus said lowermost ring will overhang said cut-out by an appreciable distance as enables the applicator to grip said overhanging portion, all as will be hereinafter more fully explained.

The radius of curvature of the rounded front-end edge 32d of said rib-like formation 32 is also chosen to correspond substantially with that of the opening of the rings R, and thus the lower half-portion 32f of said edge which has height substantially equal to the axial thickness of said rings is adapted to serve as a stop shoulder for said lowermost ring. Also, the chamfered upper half portion 32g of said edge will be chosen so that said edge portion will function as a lifting cam for a ring next above said lowermost ring when it is pushed rearwardly thereof.

It is of course well understood that in a dispenser of the type under consideration the lower end of the stack rod 10 terminates at a level just above that of the flat top surface 320 of the second-named or upper rib-like formation 32. Thus, the stack rod 10 may flex rearwardly from its normal or neutral most forward position without such rearward movement being impeded by said upper rib-like formation 32.

Whereas according to the dispenser of my prior Patent No. 2,900,107 upward-rearward movement of the ring R next above the lowermost ring of the stack thereof depended on the transversely extending, front end edges of the applicator making direct contact with and pushing against the outer edge of said next higher ring, it is a feature of the present invention that the upward-rearward movement of said next higher ring, while responsive to insertion of the applicator in the dispenser as heretofore, is entirely independent of any direct contact of the applicator therewith. More particularly, and referring first to FIGS. 1-3, the block-like formation of the base 20 mounts main and auxiliary leaf springs 40,42, respectively, which extend transversely across the path of the applicator. Said auxiliary spring 42 is disposed forwardly of and affixed at its one end to and in face engagement with the main spring 40, as by rivets 44. On the other hand, said main spring 40 comprises the free arm of an L-shaped spring member whose other right-angularly extending arm 40a is secured to the side of the upright base block 18, as by screws 46. As best seen in FIGS. 4, 5 and 6, the auxiliary spring 42 is substantially shorter than the spring 40, although long enough to extend a short distance into the path of motion of the applicator. And by reference to FIGS. 4A, 5A and 6A, it will be seen that the auxiliary spring 42 has greater vertical dimension than does the main spring 40 and more particularly that it depends downwardly from said main spring 40 by an amount such that it is engageable by a front side corner of the applicator during the course of movement of the latter into the dispenser. The aforementioned views also make it clear that the main spring 40 is disposed not only well above the lowermost ring of the stack thereof, but also well above the next higher ring of the stack. In practice, the bottom edge of the main spring 40 is at a level such that it is horizontally aligned with about the fourth or fifth ring of the ring stack.

The operation of the dispenser and its means according to the present invention for effecting both lifting and substantial rearward movement of the ring next above the lowermost ring of the stack thereof on the stack rod 10, responsive to insertion of the applicator in the dispenser to lowermost ring pick-off position, will be best understood by reference to FIGS. 46A. However, it is first explained that said applicator (designated A in FIG. 1) is generally of the type disclosed and claimed in the aforesaid Wurzel Patent No. 2,835,028, in that it comprises a blade-like member having a working end 50 which is offset angularly from the shank portion thereof and terminates in a transverse, front-end edge having a substantially semi-circular cut-out 52 formed in its central portion and a reduced thickness portion 54 extending about said cut-off which is adapted to provide a seat and backing flange bounded by an arcuate shoulder 56 for the receipt of the edge portion of a ring to be gripped,

and a leaf spring 58 secured as-by a rivet to the blade shank and whose free end is disposed to overlie the central portion of said reduced-thickness edge portion, thus resiliently-to face-grip the ring edge portion seating in the reduced-thickness portion of the blade.

It is to be understood also that the dispenser mounts more or less conventional means for guiding the bladelike working end of the applicator, upon its initial insertion in the dispenser, in a straight-line path to the lowermost ring of the stack thereof in said dispenser, such comprising a guide block 60 (FIGS. 1 land 2) secured against the top face of the base block 18 and having an upwardly opening main channel 62a and a sub-channel 62b, of which the main channel 62a has width corresponding to the width of the applicator blade, and the subchannel 62b has width and depth such as to accommodate both the ring-securing leaf spring 58 and the head of the rivet by which it is secured to the blade shank rearwardly of the applicator working end. The bottom of the main channel 62a will of course be fixed at a level such as to dispose the ring seat 54 provided in the applicator working end just at the level of the aforesaid overhanging middle-section portion of the lowermost ring of the stack supported on the support parts 28 and 30.

To insure introduction of the working end of the applicator in said main guide channel 62a at the exact angle as insures its movement forwardly to its correct ultimate ring'pick-olf position, the'invention provides additional guide means in the form of an elongate channel member 64 whose channel corresponds to and is disposed in alignment with the main channel 62a of the guide block 60, one end 66a thereof being secured in vertical position flush against the front face of the base block 18 and the other end 66b inclining forwardly-upwardly from the base block at the exact angle with respect to the main channel 62a of the guide block 60 that the working end 50 of the applicator bears to the shank portion thereof. Accordingly,

. when associated with the dispenser as in FIG. 1, and assuming all parts to be correctly dimensioned and related as intended, inserting movement of the applicator will result in, its working end being correctly positioned to engage with and pick off the lowermost ring R of the stack thereof in the dispenser.

Referring now specifically to FIGS. 4-6A, FIGS. 4, 4A show the stack rod 10 and the springs 40, 42 in their neutral position which they normally maintain prior to insertion of the applicator into the dispenser and during the early portion of such movement, said views illustrating the latter condition.

FIGS. 5 and 5A show said parts in the position which they assume upon further inserting movement of the applicator into the dispenser. That is to say, during the course of its movement from its FIGS. 4 and 4A position to its FIGS. 5 and 5A position, the forward right corner of the applicator blade has engaged the lower free edge portion of the auxiliary spring 42 and moved same rearwardly by a small amount. Such results, by virtue of the connection between said springs 40 and 42, in the main spring 40 having also moved rearwardly or towards the stack rod a distance such as brings said main spring into engagement with one or more rings mounted thereon. However, because of the vertical positioning of said main spring 40, it can engage only with rings well above both said lowermost ring and the next higher ring of the stack thereof.

FIGS. 6 and 6A show the applicator in its fully inserted position. In moving to such position from its FIGS. 5 and 5A position, the applicator, acting through the auxiliary spring 42, has moved the main spring 40 a substantial distance rearwardly. During the course of this substantial rearward movement, said main spring 40, by its engagement with rings substantially above the lowermost and next higher rings R of the stack, and solely through the intermediary of such rings, has forced the stack rod 10 to its full rearward position as determined by the lower rings of the stack above the lowermost ring abutting the aforesaid stop shoulder 32e of the rib 32. In partaking of this substantial rearward movement, not only is the ring next above the lowermost ring (which latter is held against rearward movement by the shoulder 32f of said rib 32) raised from said lowermost ring by its forceful movement against the chamfered camming edge 32g of said rib, but also it is moved to such a rearward position that the prongs p and p of said lowermost ring are disposed forwardly of the central opening of said ring next above the lowermost ring and thus beyond the point at which said prongs can possibly impede withdrawal movement of the lowermost ring now gripped by the applicator, as such gripping action is shown in FIG. 6A.

FIG. 6A illustrates another advantageous feature stemming from the above described arrangement of actuating the rings next above the lowermost ring of the stack positioned to be gripped by the applicator and its spring to an upward, substantial rearward position made possible by the present invention. More particularly, whereas the lower rings of the stack, in the normal position of the stack rod, tend to tiltforwardly-downwardly as in FIG. 4, as renders clean separation of the lowermost ring from the next higher ring more difficult than if said rings were level or tilted in the opposite direction, when the rings above the lowermost ring are pushed rearwardly to their FIGS. 6A position with rearward movement of the stack rod, they tend to tilt in the opposite direction, that is to say, their relatively forward closed ends now incline upwardly-forwardly by an amount which, while small, is nevertheless such as to further the desirable clean separation of the lowermost ring from the next highermost ring of the stack.

Without further analysis, it will be appreciated tha the improved bowed and pronged open-ring dispenser as described above achieves the desirable objectives of the invention as set forth earlier herein. However, as many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A dispenser for dispensing bowed open retaining rings having locking prongs projecting from the convex face thereof and being operable by a ring picking-off and withdrawing tool having a blade-like working end constructed and arranged as to face-grip the middle-section portion of the lowermost ring of a supply thereof disposed in vertical stack formation responsive to its insertion in the dispenser, said dispenser comprising a base having on its upper surface a support part for supporting a plurality of the rings to be dispensed arranged with their convex faces upwardly disposed and their gaps rearwardly disposed, a substantially vertically disposed flexible stack rod for maintaining a supply of said rings in vertical stack formation on said support part, means supporting said stack rod from and in a position above the base and in such manner that its lower end may flex rearwardly of the support part and of the lowermost ring of the stack thereof directly supported thereon, means on said base for guiding said tool in a fixed path and at a level such that it is disposed to move against and thereupon facegrip the middle portion of said lowermost ring, means on said support surface providing an abutment for maintaining said lowermost ring stationary against the thrust of the tool moving against same, and means responsive to movement of the tool toward said lowermost ring and being engageable only with one or more rings disposed above said lowermost and the next higher rings of the stack thereof for effecting lifting and substantial rearward movement of said next higher ring to a position as insures a clean separation of said lowermost ring from said next higher ring, thereby insuring free and unimpeded withdrawal of said lowermost ring from the stack responsive to withdrawal movement of the tool from the dispenser.

2. A dispenser according to claim 1, wherein said last means includes a horizontally disposed leaf spring mounted to said base in position such that its free end is disposed above said lowermost and next higher rings and normally a small distance forwardly of said one or more rings above same, and means operatively connected to said leaf spring and disposed in the path of inserting movement of the tool but effectively to the side of the ring stack for translating inserting movement of the tool into rearward flexing of the free end of the leaf spring against said one or more rings and thereby rearward flexure of the stack rod by an amount as insures clean separation of said lowermost from said next higher ring as aforesaid.

3. A dispenser according to claim 2, wherein said translating means comprises a second leaf spring connected to said first-named leaf spring in position such that its free end extends a short distance only into the path of tool movement, thereby to be abutted by and flexed rearwardly by the tool during the course of its inserting movement,

the construction and arrangement being such that flexure of said second leaf spring effects flexure of said firstnamed spring as aforesaid.

4. A dispenser according to claim 1, and further mounting means extending forwardly from said base for guiding the working end of the tool to said tool guiding means on the base and for initially dispensing the working end of said tool at the proper angle for its movement along said fixed path to ring pick-off position.

5. The combination of a dispenser for dispensing bowed open retaining rings of the type having locking prongs extending from the convex face thereof and a ring pickoff and withdrawing tool for effecting withdrawal from said dispenser of the lowermost ring of a plurality of such rings maintained in stack formation in the dispenser, said dispenser comprising a base having on its upper surface a support part for supporting the plurality of rings to be dispensed arranged with their convex faces upwardly disposed and their gaps rearwardly disposed, a substantially vertically disposed flexible stack rod for normally maintaining said rings in vertical stack formation on said support part, means supporting said stack rod from and in a position above the base and in such manner and at a level such that its lower end is spaced a clearance distance above said support part and may flex rearwardly both of said support part and of the lowermost ring of a stack thereof held by said support part, said tool comprising a blade-like member having ring-seating means in its front edge and carrying spring means for securing a ring whose outer edge portion is seated in said ringseating means, said dispenser base being provided with means for guiding said tool along a fixed path extending to and at a level such that its ring-seating means is disposed in horizontal alignment with the lowermost ring of the stack, said support part including means providing an abutment for maintaining said lowermost ring of the stack stationary against the thrust of the applicator moving thereagainst, and means actuable by said applicator during its inserting movement along said path and engageable with rings of the stack disposed well above the lowermost and the next higher rings of said stack for effecting lifting and rearward movement of said next higher ring to a position as insures clean separation of said lowermost ring from said next higher ring and thereby unimpeded withdrawal movement of said lowermost ring from the support par-t responsive to withdrawal of the tool from the dispenser.

6. The combination according to claim 5,wherein said last means includes a horizontally disposed leaf spring mounted to said base in position such that its free end is disposed above said lowermost and next higher rings and normally a small distance forwardly of said one or more rings above same, and means operatively connected to said leaf spring and disposed in the path of movement of the working end of the tool but effectively to the side of the ring stack for translating inserting movement of the tool into rearward of the free end of said leaf spring against said one or more rings and thereby rearward flexure of the stack rod by an amount as insures the clean separation of said lowermost ring from said next higher ring as aforesaid.

7. The combination according to claim 6, wherein said translating means comprises a second leaf spring connected to said first-named leaf spring in position such that it extends a short distance only into the path of tool movement, thereby to be abutted and flexed rearwardly by the tool during the course of its inserting movement, the construction and arrangement being such that flexure of said second leaf spring effects flexure of said firstnarned spring into engagement with said one or more rings of the stack as aforesaid. V .8. The combination according to claim 5, wherein the base mounts means extending forwardly therefrom for guiding the blade-like working end of the tool to said guide path and further for initially disposing said working end at the proper angle for its movement along said fixed path to ring pick-off position.

References Cited by the Examiner UNITED STATES PATENTS 2,712,398 7/1955 Erdmann 221-220 2,819,818 1/1958 Erdmann 221-220 2,900,107 8/1959 Erdmann 221-220 3,058,596 10/1962 Coldren 211-59 RAPHAEL M. LUPO, Primary Examiner. W. SOBIN, Assistant Examiner. 

1. A DISPENSER FOR DISPENSING BOWED OPEN RETAINING RINGS HAVING LOCKING PRONGS PROJECTING FROM THE CONVEX FACE THEREOF AND BEING OPERABLE BY A RING PICKING-OFF AND WITHDRAWING TOOL HAVING A BLADE-LIKE WORKING END CONSTRUCTED AND ARRANGED AS TO FACE-GRIP THE MIDDLE-SECTION PORTION OF THE LOWERMOST RING OF A SUPPLY THEREOF DISPOSED IN VERTICAL STACK FORMATION RESPONSIVE TO ITS INSERTION IN THE DISPENSER, SAID DISPENSER COMPRISING A BASE HAVING ON ITS UPPER SURFACE A SUPPORT PART FOR SUPPORTING A PLURALITY OF THE RINGS TO BE DISPENSED ARRANGED WITH THEIR CONVEX FACES UPWARDLY DISPOSED AND THEIR GAPS REARWARDLY DISPOSED, A SUBSTANTIALLY VERTICALLY DISPOSED FLEXIBLE STACK ROD FOR MAINTAINING A SUPPLY OF SAID RINGS IN VERTICAL STACK FORMATION ON SAID SUPPORT PART, MEANS SUPPORTING SAID STACK ROD FROM AND IN A POSITION ABOVE THE BASE AND IN SUCH MANNER THAT ITS LOWER END MAY FLEX REARWARDLY OF THE SUPPORT PART AND OF THE LOWERMOST RING OF THE STACK THEREOF DIRECTLY SUPPORTED THEREON, MEANS ON SAID BASE 